This Telephone Voice Changer disguises your voice by digitizing it. The degree of change can be adjusted as you are speaking by pressing the button located on the front of the unit. Features 6 different voices and an on/off switch. Battery is included. Dimensions: Just 2" x 1" x 3/4". Easy hook up and is compatible with all telephones because you simply hold it over the mouthpiece and speak normally. Change your voice to a robot, little girl, old man, donald duck and more. This unit is superior to the white hand held voice changer widely seen on the internet. Please note, this unit must be placed flush over the mouthpiece of the phone to work properly. It will not work well as a stand alone voice changer. Ships only to verified credit card billing address. Ships to USA addresses only. Does not ship by air